Last week, 20 leaders responsible for 85 percent of the world's economy and two-thirds of the population gathered at the G-20 Summit in Buenos Aires. The stage was set to decide on a better way forward on matters like international trade, the global economy, and food security. So, you know, just another Friday.

Climate change was an important topic on this year's agenda, which comes on the heels of an ominous climate report by the United Nations and the World Meteorological Organization's announcement that the average global temperature for 2018 will likely be the fourth highest on record, and 20 of the world's warmest years happened in the last 22 years. If that wasn't bad enough, the top four warmest years happened over the last four years.

Host President Argentina's Mauricio Macri kicked off the summit by announcing, "I am an optimist"—and there were certainly some positive strides made at the gathering. One of the most notable being an agreement by 19 nations (the United States is the only one that didn't sign on) to uphold the Paris Climate Agreement and "continue to tackle climate change while promoting sustainable development and economic growth."

If you're shaking your head that President Trump still isn't on board with the accord, know that the U.S. at least agreed to sign on to a measure to support clean energy initiatives that reads, "We recognize the crucial role of energy in helping shape our shared future, and we encourage energy transitions that combine growth with decreasing greenhouse gas emissions toward cleaner, more flexible and transparent systems, and cooperation in energy efficiency."

Every signee has a different role to play, and the nitty-gritty of how they will work to keep global warming to under 2 degrees Celsius compared to preindustrial levels is the source of conversation at the COP24 climate talks, which just kicked off in Katowice, Poland, and will go on until December 14. (Yep, it's a big time for climate policy right now—and you can follow along with it here.)

"The upcoming climate talks are the most important round of negotiations since the Paris Agreement was reached three years ago," Lou Leonard, the World Wildlife Fund's senior vice president for climate change and energy, told CNBC of the talks that gather thousands of world leaders, activists, and policymakers to flesh out a framework for the Paris Climate Agreement. 2018 is the year the countries committed to putting a plan in place for carrying out the agreement, so time is running out.

Many experts are saying that the Paris Agreement isn't nearly aggressive enough, especially considering the extreme weather events that prove that we are already facing the forceful and frightening effects of global warming. Ahead of the meeting, leaders from 16 European countries called for more aggressive policies to combat climate change, which they refer to as "the key challenge of our time." Now, it's all eyes on Poland.